6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx> commit a81dbd0463eca317eee44985a66aa6cc2ce5c101 upstream. Set the receiver level to something > 0 before calling imx_uart_start_rx in rs485_config. This is necessary to avoid an interrupt storm that might prevent the system from booting. This was seen on an i.MX7 device when the rs485-rts-active-low property was active in the device tree. Fixes: 6d215f83e5fc ("serial: imx: warn user when using unsupported configuration") Cc: stable <stable@xxxxxxxxxx> Signed-off-by: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx> Link: https://lore.kernel.org/r/20240621153829.183780-1-eichest@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/imx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -1978,8 +1978,10 @@ static int imx_uart_rs485_config(struct /* Make sure Rx is enabled in case Tx is active with Rx disabled */ if (!(rs485conf->flags & SER_RS485_ENABLED) || - rs485conf->flags & SER_RS485_RX_DURING_TX) + rs485conf->flags & SER_RS485_RX_DURING_TX) { + imx_uart_setup_ufcr(sport, TXTL_DEFAULT, RXTL_DEFAULT); imx_uart_start_rx(port); + } return 0; }